Combined structural refinement and spontaneous polarization study of Bi(3.5)Ce(0.5)Ti(3)O(12) by using x-ray and neutron powder diffraction data

Abstract

Combined structural refinement of Bi(3.5)Ce(0.5)Ti(3)O(12) was carried out by using both neutron and x-ray diffraction results based on the monoclinic space group of B1a1. Weighted R-factors were 6.29% and 8.17% for the neutron and x-ray diffraction data, respectively. The goodness-of-fit indicator (S) was 1.9 for all patterns. Lattice parameters were a = 5.4229(6) angstrom, b = 5.4038(6) angstrom and c = 32.8838(5) angstrom. The beta angle was 90.10(1)degrees. Spontaneous polarization (P(s)) calculated from the refinement results was 26.7 mu C cm(-2). The contribution of each atom on the spontaneous polarization was plotted and it was clearly shown that the distortion of TiO(6) octahedrons was the key factor that determines spontaneous polarization.